In the fields of measuring, inspection, bonding, welding and machining, clamps are used for holding work pieces together or holding a work piece on a work surface. Various types of clamps are available, such as bar clamps, C-clamps, F-clamps and screw clamps. These clamps generally comprise a fixed arm with a fixed clamping pad, a movable arm with a clamping pad, or a fixed arm with a fixed clamping pad at one end and a movable clamping pad attached directly to the other end of the fixed arm. Bar clamps utilize a sliding arm over the fixed arm to clamp a work piece.
Different types of quick locking and quick releasing mechanisms for the sliding arm are available in the field. A C-clamp consists of a C-shaped fixed arm with a clamping pad at one end and a threaded rod at the other end, the threaded rod having a clamping pad at one end and a cranking handle at the other end. The movable arm of an F-clamp is a straight arm with one end sliding over the L-shape fixed arm and the other end feeding a threaded rod with a clamping pad. A screw clamp utilizes two parallel clamping arms opened and closed by two parallel screws.
To clamp a work piece to the surface of a work surface, these conventional clamps must be used at the edge of the work surface so that one of the clamping arms will cross over the edge and reach the bottom of the working surface of the bench.
Conventional clamps utilized for clamping at the edge of a work surface, when used for securing precision measuring instruments are less than ideal in supplying a rigid stable platform in applications that necessitate precise tolerances in the fields of measuring and inspection.